PM Test Method Amendments Proposed: An end to the transition period for CPM?

On March 25, 2009, EPA proposed amendments to Test Methods 201A and 202, as contained in 40 CFR 51, Appendix M. The proposed amendments to Method 201A, which is a standard method for quantifying filterable PM10 emissions, allow for the addition of a PM2.5 cyclone to allow for sampling and quantification of filterable PM2.5 emissions. The proposed amendments to Method 202, which is the standard method for quantifying condensable particulate matter (CPM) emissions, revise the sample collection and recovery procedures to reduce by as much as 90 percent the formation of sulfate artifacts that could lead to inaccurate measurement (i.e., positive bias) of CPM emissions.

The proposed amendments to Method 202 could also signal the approaching end of a facility's ability to ignore CPM emissions under the New Source Review program. Specifically, as part of the PM2.5 implementation rule, which was published in May 2008, EPA announced that CPM emissions need not be considered in the quanitification of PM2.5 until test methods for this pollutant are validated, or January 1, 2011, whichever is earlier. With the new proposed rule, EPA is now soliciting comments on whether to end the transition period within 60-90 days after the proposed changes to Method 202 are finalized.